Working with Views

What are Views?

Virtual tables based on SQL queries that simplify complex data access.

CREATE VIEW

CREATE VIEW employee_summary AS
SELECT e.first_name, e.last_name, d.department_name, e.salary
FROM employees e
JOIN departments d ON e.department_id = d.department_id;

Using Views

SELECT * FROM employee_summary WHERE salary > 60000;

Benefits

• Simplify complex queries
• Provide data security
• Present consistent interface
• Hide table complexity

Types

• Simple Views: Based on single table
• Complex Views: Multiple tables with joins/functions
• Materialized Views: Physically stored results

DROP VIEW

DROP VIEW employee_summary;

Best Practices

• Use descriptive names
• Document view purpose
• Consider performance impact
• Regular maintenance for complex views